Add inline code examples in plotting module docstrings

[willschlitzer]

As mentioned in this comment, this is a checklist to add inline code examples in the plotting module docstrings.

• basemap
• choropleth
• coast (Add inline example for coast #2142)
• colorbar (Add inline example for colorbar #2373)
• contour Figure.contour: Add an inline example #4934
• directional_rose
• fill_between
• grd2cpt (Add inline example for grd2cpt #2145)
• grdcontour (Add inline example for grdcontour #2148)
• grdimage (Add inline example for grdimage #2146)
• grdview (Add inline example for grdview #2381)
• histogram
• hlines
• image
• inset
• legend Figure.legend: Add an inline example #4930
• logo
• magnetic_rose
• meca Figure.meca: Add an inline example #4929
• paragraph
• plot Figure.plot: Add an inline example #4932
• plot3d Figure.plot3d: Add an inline example #4933
• pygmtlogo
• rose
• scalebar
• solar (Add inline example for solar #2147)
• subplot Figure.subplot: Add an inline example #4938
• ternary Figuer.ternary: Add an inline example #4931
• text Figure.text: Add an inline example #4937
• tilemap Figure.tilemap: Add two inline examples #4928
• timestamp
• velo
• vlines
• wiggle Figure.wiggle: Add an inline example #4936

Are you willing to help implement and maintain this feature? Yes

[seisman]

Hmmm, do we really need to add inline examples for these plotting modules?

Looking at the inset documentation, I think the visual examples at the bottom are more useful than the code example.

[willschlitzer]

I thought the general attitude was that inline examples should still be added to plotting modules. My thought it that working code is provided on the function's page without the need to click around to other examples.

@meghanrjones @weiji14 Thoughts?

[weiji14]

The visual examples at the bottom are indeed more useful, but I think it's worth having an example in the docstring as well (e.g. for people working offline). That said, definitely lower on the priority list for now, something for PyGMT v0.8.0 or v0.9.0.